>>> [!note] Migrated issue <!-- Drupal.org comment --> <!-- Migrated from issue #3263602. --> Reported by: [catch](https://www.drupal.org/user/35733) >>> <h3 id="summary-problem-motivation">Problem/Motivation</h3> <p>There are cases where we use value objects, or where providing an interface for an otherwise one-off class will do more harm than good. </p> <h3 id="summary-benefits">Benefits</h3> <p>If we adopted this change, the Drupal Project would benefit by ...</p> <h3 id="summary-supporters">Three supporters required</h3> <ol> <li><a href="https://www.drupal.org/u/">https://www.drupal.org/u/</a>{userid} (yyyy-mm-dd they added support)</li> <li><a href="https://www.drupal.org/u/">https://www.drupal.org/u/</a>{userid} (yyyy-mm-dd they added support)</li> <li><a href="https://www.drupal.org/u/">https://www.drupal.org/u/</a>{userid} (yyyy-mm-dd they added support)</li> </ol> <h3 id="summary-proposed-changes">Proposed changes</h3> <p>Provide all proposed changes to the Drupal <a href="https://www.drupal.org/docs/develop/standards">Coding standards</a>. Give a link to each section that will be changed, and show the current text and proposed text as in the following layout:</p> <h4>1.<a href="https://www.drupal.org/docs/develop/standards/coding-standards#s-objects">https://www.drupal.org/docs/develop/standards/coding-standards#s-objects</a></h4> <h5>Current text</h5> <blockquote><p> Use an interface typehint for parameter and return types (not a class). Typehint the most specific interface that encompasses all possible parameter or return values. Do not use stdClass. </p></blockquote> <h5>Proposed text</h5> <blockquote><p> Use an interface typehint for parameter and return types where available. Typehint the most specific interface or class that encompasses all possible parameter or return values. </p></blockquote> <h4>2. <a href="https://www.drupal.org/docs/develop/standards/php/object-oriented-code#interfaces">https://www.drupal.org/docs/develop/standards/php/object-oriented-code#interfaces</a></h4> <h5>Current text</h5> <blockquote><h2 id="interfaces">Use of interfaces</h2> <p>The use of a separate interface definition from an implementing class is strongly encouraged because it allows more flexibility in extending code later. A separate interface definition also neatly centralizes documentation making it easier to read. All interfaces should be fully documented according to <a href="http://drupal.org/node/1354#classes">established documentation standards</a>.</p> <p>If there is even a remote possibility of a class being swapped out for another implementation at some point in the future, split the method definitions off into a formal Interface. A class that is intended to be extended must always provide an Interface that other classes can implement rather than forcing them to extend the base class.</p> </blockquote> <h5>Proposed text</h5> <p>None. The text is to be deleted.</p> <h4>3. <a href="https://www.drupal.org/docs/develop/standards/php/object-oriented-code#hinting">https://www.drupal.org/docs/develop/standards/php/object-oriented-code#hinting</a></h4> <h5>Current text</h5> <blockquote><h2 id="hinting">Type hinting</h2> <p>PHP supports optional type specification for function and method parameters for classes and arrays. Although called "type hinting" it does make a type required, as passing an object that does not conform to that type will result in a fatal error.</p> <ul> <li>DO specify a type when conformity to a specific interface is an assumption made by the function or method. Specifying the required interface makes debugging easier as passing in a bad value will give a more useful error message.</li> <li>DO NOT use a class as the type in type hinting. If specifying a type, always specify an Interface. That allows other developers to provide their own implementations if necessary without modifying existing code.</li> </ul> <p>Example:</p> <pre> <div class="codeblock"><code class="language-php">// Correct:<br>function make_cat_speak(FelineInterface $cat) {<br>&nbsp; print $cat-&amp;gt;meow();<br>}<br><br>// Wrong:<br>function make_cat_speak(GarfieldTheCat $cat) {<br>&nbsp; print $cat-&amp;gt;meow();<br>} <h5>Proposed text</h5> <p>None. The text is to be deleted.</p> <h3 id="summary-remaining-tasks">Remaining tasks</h3> <p>\<br> Needs examples.</p> <ol> <li><del>Create this issue in the Coding Standards queue, using the defined template</del></li> <li>Add supporters</li> <li>Create a Change Record</li> <li>Review by the Coding Standards Committee</li> <li>Coding Standards Committee takes action as required</li> <li>Discussed by the Core Committer Committee, if it impacts Drupal Core</li> <li>Final review by Coding Standards Committee</li> <li>Documentation updates <ol> <li>Edit all pages</li> <li>Publish change record</li> <li>Remove 'Needs documentation edits' tag</li> </ol> </li> <li>If applicable, create follow-up issues for PHPCS rules/sniffs changes</li> </ol> <p>For a full explanation of these steps see the <a href="https://www.drupal.org/project/coding_standards" title="Coding Standards project page">Coding Standards project page</a></p> <p>Possible follow up to remove to remove https://www.drupal.org/docs/develop/standards/object-oriented-code.</p> </code></div></pre></blockquote>